Yukon Gear Dura Grip For GM & Chrysler 11.5in / 30 Spline

The American Axle 11.5 inch rear end sits under a lot of work trucks: Chevrolet and GMC 2500HD and 3500 pickups from 2001 on, and Ram 2500 and 3500 trucks from 2003 on. Many left the factory with an open differential, and owners notice it the first time a loaded trailer spins one rear tire on a wet ramp or a gravel lot. The Yukon Dura Grip YDGGM11.5-30-1 is a clutch-type limited slip for that axle with 30-spline shafts. It replaces the open carrier or a worn factory unit and sends torque to the tire that has grip, while still letting the wheels differentiate in turns.

What the Dura Grip does in an AAM 11.5

An open differential always splits torque evenly, so the side with the least traction sets the limit and the other tire just sits there. The Dura Grip adds clutch packs behind each side gear. Preload and the separating force of the gears squeeze those packs, which ties the two axle shafts together until the difference in traction is large enough to slip them. Yukon builds this unit with a nodular iron case, four forged 4320 chromoly spider gears in a four-pinion layout and composite clutches, and it is fully rebuildable and assembled in the USA. Yukon lists it for all gear ratios on the 11.5 with 30-spline axles, so a ratio change does not require a different case. Unlike a selectable locker it needs no air or wiring, and unlike a full locker it stays smooth on dry pavement with a heavy truck.

Symptoms that send owners to a limited slip

• One rear tire spinning when backing a trailer up a wet or gravel ramp
• A factory limited slip that no longer pulls both wheels, often after years of the wrong gear oil or no additive
• Chatter or clunk in tight turns from a worn clutch-type unit
• Metal in the drain plug or on the cover from a failing original carrier
• Pinion and carrier bearing whine, the common 11.5 wear item, discovered when the cover comes off for a carrier swap

How to confirm what you have before ordering

Jack one rear wheel off the ground with the transmission in neutral and turn it by hand. If the other side turns the opposite direction freely, it is open; if it resists or turns the same way, there is a limited slip already in there. Confirm the axle is the AAM 11.5: it has a 14-bolt cover, which leads many people to confuse it with the older GM 10.5 14-bolt. Our comparison of the GM 14-bolt and AAM 11.5 shows how to tell them apart, and the AAM 11.5 problems and rebuild cost page covers the bearing and seal failures worth fixing while the carrier is out. Check the axle tag for the ratio and count the axle shaft splines; this unit is 30 spline.

Fitment

Yukon lists the YDGGM11.5-30-1 for GM and Chrysler AAM 11.5 inch rear differentials with 30-spline axle shafts, all gear ratios. That covers the common 2001-and-later GM 2500HD and 3500 and 2003-and-later Ram 2500 and 3500 11.5 rears with 30-spline shafts. Later trucks changed: newer GM heavy-duty 11.5 axles moved to a different spline count, and late-model Ram 3500s can be built with an 11.5, 11.8 or 12 inch rear, so read the axle tag and count splines before ordering. If you are unsure, send us your year and VIN. The unit weighs about 56 pounds and ships calculated freight from the USA. For other carrier choices on this axle, compare the Yukon Grizzly locker for the 11.5 and the gear-driven Yukon helical positraction, or browse axle hard parts.

Install notes

• Setting up a carrier is gear-shop work: new carrier bearings, carrier shims to set backlash and preload, and a contact pattern check. Plan on doing it with an overhaul kit such as the Yukon master overhaul kit for 2010-and-older 11.5 axles; later axles use different kits.
• The axle shafts come out to remove the carrier, so it is the right time to replace wheel bearings and seals with the Yukon 11.5 axle bearing and seal kit.
• Use new ring gear bolts with thread locker and torque them to the specification in your service data.
• Fill with the gear oil and limited-slip friction modifier Yukon specifies in the instructions supplied with the unit. Our friction modifier guide explains why the clutches chatter without it.
• Break the clutches in gently: no heavy towing for the first few hundred miles, then change the gear oil.

Will this fit my 2020 or newer Chevy 2500HD?

Check the spline count first. This unit is for AAM 11.5 axles with 30-spline shafts. Newer GM heavy-duty 11.5 axles changed spline count, so send us your VIN if you are not sure.

Do I need a different unit for my gear ratio?

No. Yukon lists this Dura Grip for all gear ratios on the 11.5 with 30-spline axles.

Is a Dura Grip a locker?

No. It is a clutch-type limited slip. It biases torque to the tire with grip but still lets the wheels turn at different speeds, so it drives smoothly on pavement. A full locker like the Grizzly locks both sides together.

What gear oil should I use?

Follow the instructions supplied with the unit for gear oil type and limited-slip friction modifier. Running it without the right additive is the usual cause of chatter in turns.

Can the Dura Grip be rebuilt later?

Yes. Yukon designs the Dura Grip to be fully rebuildable, and replacement composite clutch kits are made for the 11.5 version.

What else should I replace while the carrier is out?

New carrier bearings and shims from an overhaul kit, axle bearings and seals, ring gear bolts and the cover gasket or sealant. Inspect the pinion bearings, since whine there is a common 11.5 complaint.